In the core and probe management settings, you can define settings for the core server as well as for probe connections if you use remote or mini probes.

If you cannot save changes to Core & Probes settings because you get an Error (Bad Request) with the message Active Directory Domain not accessible, ensure you provide the correct access type for your domain in section Active Directory Integration! For example, change from "local user" to Use explicit credentials and provide correct credentials for the domain. Please note that PRTG automatically sets the access type "local system" by default, so you might need to change this.

If you use PRTG on premises and open the system administration page from another administration page, PRTG will ask you to enter your credentials again for security reasons if 15 minutes (900 seconds) have passed since your last credential-based login. A dialog box will appear. Enter your Login Name and Password for PRTG in the corresponding fields and confirm to continue.

Core and Probes Settings

This documentation refers to the PRTG System Administrator user accessing the PRTG web interface on a master node. If you use other user accounts, interfaces, or nodes, you might not see all of the options in the way described here. If you use a cluster installation, note that failover nodes are read-only by default.

Proxy Configuration

This option is not available in PRTG hosted by Paessler.

Use Proxy Server

We recommend that you use PRTG with a direct internet connection. However, if you need to use a proxy, you can configure the relevant settings here. Choose between:

No, use direct connection to the internet (default): Do not use a proxy. Use this setting if there is a direct internet connection available to the server running the PRTG core server.

This setting is only visible if proxy credentials are enabled above. Enter a username for proxy authentication. Please enter a string.

Password

This setting is only visible if proxy credentials are enabled above. Enter a password for proxy authentication. Please enter a string.

Probe Connection Settings

Probe Connections IPs

Define how PRTG handles incoming connections from probes. Choose between the following options:

Local Probe only, 127.0.0.1 (PRTG will not be accessible for remote probes): The PRTG core server only accepts local probe connections. You cannot use remote probes with this setting enabled. This is the default setting in PRTG on premises.

All IPs available on this computer: The PRTG server will always accept incoming connections from remote probes, no matter on which IP address of the core server they come in. This is the default setting in PRTG hosted by Paessler.

Specify IPs: The PRTG server will accept incoming connections from remote probes only on the selected IP address(es) of the core server. In the list, select the IP addresses by adding a check mark in front of the desired IPs.

If you change this setting, PRTG needs to restart the core server to apply your changes. After clicking the Save button, a dialog box appears that asks you to confirm the required core server restart. Click OK to trigger the restart and follow the instructions on the screen. During the restart, all the users of the PRTG web interface, of the Enterprise Console, or of PRTG Apps for Mobile Network Monitoring will be disconnected and reconnected.

This option is not available in PRTG hosted by Paessler.

Access Keys

Enter a list of access keys, one per line. Every (remote) probe that wants to connect to this PRTG installation has to use one of these keys.

Enter a list of remote probe IPs or DNS names that will be accepted when connecting to this PRTG installation. Provide one IP address or DNS name per line. The local probe (127.0.0.1) is always allowed automatically. PRTG will check the list of allowed addresses first before the list of denied addresses.

[Empty]: An empty field does not allow any remote probes (but only the local probe). Please enter IP addresses or DNS names to allow remote probe connections.We recommend that you use IP addresses rather than DNS names, because DNS name resolution may be cached.

any: Enter the word any to automatically allow all remote probe connections. This is the default setting in PRTG hosted by Paessler.We recommend that you only use this option in intranets in PRTG on premises!

If the IP address of your remote probe changes regularly (for example, due to an internet provider assigning IP addresses dynamically), please enter the potential IP range for this remote probe or use the any option.

You can use the PRTG syntax for IP address ranges here. For more information, see section Define IP Ranges.

Deny IPs

Enter a list of remote probe IPs or DNS names that will notbe accepted when connecting to this PRTG installation. Provide one IP address or DNS name per line. This is useful to explicitly deny connections from certain remote probes you do not want to include in your setup anymore (for example, for a certain time).

Access to IP addresses or DNS names you allowed above will be denied if you enter them here. This is useful to allow access to an IP range in the field above, but deny access to a single IP address. You can use the PRTG syntax for IP address ranges here (see section Define IP Ranges).

We recommend that you use IP addresses rather than DNS names, because DNS name resolution may be cached.

Deny GIDs

Enter a list of GIDs, one global ID (GID) per line. The access to matching GIDs will be denied. If you remove a remote probe from the device tree or if you deny a remote probe after installation, its GID will be automatically entered here. This specific remote probe will not be able to connect anymore. Denying GIDs is more precise than denying IPs, where other remote probes at the same location could be excluded too.

What is a global ID (GID)? It is the ID that PRTG Network Monitor attributes to every device that you include in your monitoring.

Connection Security

Specify the security level that will be used for connections from and to the PRTG core server. Choose between:

High security (TLS 1.2): The web server will only accept high security connections from probes.

Weakened security (SSL V3, TLS 1.0, TLS 1.1, TLS 1.2): If you have probes that do not support high or default security connections because you updated from an older PRTG version, you can choose this security level to connect and update older probes. After updating, we recommend that you use the default or high security setting.

If you change this setting, PRTG needs to restart the core server to apply your changes. After clicking the Save button, a dialog box appears that asks you to confirm the required core server restart. Click OK to trigger the restart and follow the instructions on the screen. During the restart, all the users of the PRTG web interface, of the Enterprise Console, or of PRTG Apps for Mobile Network Monitoring will be disconnected and reconnected.

This option is not available in PRTG hosted by Paessler.

Mini Probes

Define if you want to allow Mini Probe connections to your PRTG server. If you want to use Mini Probes, you need to set up your PRTG web server to accept connections of Mini Probes here and choose the secure HTTPS server option in the web server settings. Choose between:

No Mini Probes: Mini Probes cannot connect to your PRTG web server. You are not able to monitor with Mini Probes if you choose this option.

Allow Mini Probes to connect to the web server: Mini Probes can connect to your PRTG web server and use the defined TCP port for the web server for this purpose. The default port for SSL connections is 443.

Allow Mini Probes to connect to an extra port: Mini Probes can connect via a specific port to your PRTG web server. This is useful if you do not want to have your whole PRTG web server reachable from other networks all the time only because of Mini Probes.SSL is always required to be active on the Mini Probe port.

If you change this setting, PRTG needs to restart the core server to apply your changes. After clicking the Save button, a dialog box appears that asks you to confirm the required core server restart. Click OK to trigger the restart and follow the instructions on the screen. During the restart, all the users of the PRTG web interface, of the Enterprise Console, or of PRTG Apps for Mobile Network Monitoring will be disconnected and reconnected.

This option is not available in PRTG hosted by Paessler.

Mini Probe Port

This field is only visible if you select the extra Mini Probe port option above. Enter the number of the port that you want to use for Mini Probe connections. Ensure that SSL is available on this port.

If you change this setting, PRTG needs to restart the core server to apply your changes. After clicking the Save button, a dialog box appears that asks you to confirm the required core server restart. Click OK to trigger the restart and follow the instructions on the screen. During the restart, all the users of the PRTG web interface, of the Enterprise Console, or of PRTG Apps for Mobile Network Monitoring will be disconnected and reconnected.

Define which user account PRTG will use to configure Active Directory (AD) access. PRTG uses this account to query the AD for existing groups. Choose between:

Use the PRTG core service account (usually LOCAL SYSTEM): Use the same Windows user account configured for the "PRTG Core Server Service". In a default installation, this is the "local system" Windows user account. If this account does not have the right to query all groups of your Active Directory, do not use this option.

Use explicit credentials: Define a user account that PRTG will use to authenticate against the Active Directory. This should be a user account with full access to all of your Active Directory groups.

Access User

This field is only visible if you enable the use of explicit credentials above. Enter the Windows user account name that PRTG will use to authenticate for Active Directory configuration.

Access Password

This field is only visible if you enable the use of explicit credentials above. Enter the password for the Windows user account that PRTG will use to authenticate for Active Directory configuration.

Historic Data Purging: Define for how many days historic data remains accessible

Data purging enables you to automatically delete unnecessary data to free up disk space and improve system performance. You can define different time spans for several kinds of data. Select here for how many days historic data remains accessible.

For further information on storage locations, see section Data Storage.

Define how long records in the system logfile Log Database.db will be kept. Enter a value in days. All entries older than this value will be deleted from the logfile automatically. This also affects the content of the Logs tab of monitoring objects like sensors. Keep this value as low as possible to enhance system performance.

Default value is 30 days.

Web Server Log Records

PRTG creates one web server logfile every day. Define how many web server logfiles are kept. Enter a value in days. All web server logfiles older than this value will be deleted automatically.

Default value is 30 days.

Historic Sensor Data

Define for how many days historic sensor data are kept for all sensors. It is used to create reports of monitoring data. Enter a value in days.

Depending on the used intervals and the number of sensors in your setup, the file containing this data can become large. For smaller installations (500 sensors or less) a value of 365 is usually fine.

Historic sensor data is the basis for reports on monitoring data. If you decrease this value, there will be less historic monitoring data available!

Default value is 365 days.

Toplist Records

Define how long toplist records for Flow and Packet Sniffer sensors are kept. Enter a value in days. We recommend that you use 30 days here.

Old toplist data will be purged automatically as soon as a limit of 2 GB is reached. The oldest data is deleted first from the database.

Default value is 30 days.

Closed Tickets

Define how long tickets that are in status closed are kept. Enter a value in days.

Default value is 365 days.

Reports

Reports generated in PDF format are stored on disk for later reference. Define the maximum age for these reports. Enter a value in days. All reports older than this value are deleted automatically.

Default value is 365 days.

Configuration Auto-Backups

PRTG creates one backup of your configuration every day. Define the maximum age for these backups. Enter a value in days. All configuration backup files older than this value will be deleted automatically.

Default value is 365 days.

Screenshots of HTTP Full Web Page Sensor

Define how long the screenshots of the HTTP Full Web Page sensor (PhantomJS browser engine) are kept. Enter a value in days. PRTG will delete older screenshots with every sensor scan.

Default value is 10 days.

Save your settings. If you change tabs or use the main menu, all changes to the settings will be lost!